ALSA
To use ALSA, install the alsa-utils
package and make sure your user is a
member of the audio
group.
The alsa-utils
package provides the alsa
service. When enabled, this service
saves and restores the state of ALSA (e.g. volume) at shutdown and boot,
respectively.
To allow use of software requiring PulseAudio, install the apulse
package.
apulse
provides part of the PulseAudio interface expected by applications,
translating calls to that interface into calls to ALSA. For details about using
apulse
, consult the project
README.
Configuration
The default sound card can be specified via ALSA configuration files or via kernel module options.
To obtain information about the order of loaded sound card modules:
$ cat /proc/asound/modules
0 snd_hda_intel
1 snd_hda_intel
2 snd_usb_audio
To set a different card as the default, edit /etc/asound.conf
or the per-user
configuration file ~/.asoundrc
:
defaults.ctl.card 2;
defaults.pcm.card 2;
or specify sound card module order in /etc/modprobe.d/alsa.conf
:
options snd_usb_audio index=0
Dmix
The dmix
ALSA plugin allows playing sound from multiple sources. dmix
is
enabled by default for soundcards which do not support hardware mixing. To
enable it for digital output, edit /etc/asound.conf
:
pcm.dsp {
type plug
slave.pcm "dmix"
}